Heatable package with multi-purpose valve and method of manufacture

Abstract

A package for a product having a multi-purpose valve includes a valve having a tubular body that defines a recess between open and closed ends, and the closed end includes an aperture for venting a pressurized gases therethrough. A retaining member operative for snap-fit engagement with the tubular body is spaced from the closed end of the tubular body. A breathable membrane element is positioned between the tubular body closed end tubular body and the retaining member. The breathable membrane element is positioned adjacent the closed end for respiring a gas from the product through the membrane to maintain a predetermined a concentration of oxygen and a predetermined concentration of carbon dioxide within the package. The membrane element is displaceable from the closed end to allow pressurized gases to pass through the closed end aperture during heating of the package.

1 . A flexible pouch for packaging a product contained therein, the pouch comprising:
 a panel of flexible material forming a body of the pouch; and   a multi-purpose valve assembly disposed in the panel, wherein the valve assembly includes:   a tubular body having an open end and a closed end that defines a recess between the open and closed ends, and the closed end includes an aperture for venting a pressurized gas therethrough,   a retaining member operative for snap-fit engagement with the tubular body that is spaced apart from the closed end of the tubular body,   a breathable membrane element having a plurality of apertures that is positioned between the closed end of the tubular body and the retaining member, such that the breathable membrane element is positioned adjacent the closed end for respiring a gas from the product through the plurality of apertures in the membrane element at a predetermined transmission rate, to maintain a predetermined concentration of oxygen and a predetermined concentration of carbon dioxide within the pouch during storage of the pouch.   
     
     
         2 . The flexible pouch of  claim 1 , wherein the membrane element is displaceable from the closed end to vent a pressurized gas through the closed end aperture during heating of the pouch above a predetermined threshold temperature. 
     
     
         3 . The flexible pouch as set forth  claim 1  wherein the membrane element is a polypropylene material having a predetermined number of apertures of a predetermined size, to control the transmission rate of gas from the product during storage. 
     
     
         4 . The flexible pouch as set forth  claim 1  wherein the membrane element is a cast polypropylene material having a predetermined number of apertures of a predetermined size, to control the transmission rate of gas from the product during storage. 
     
     
         5 . The flexible pouch of  claim 1 , wherein the pouch includes multiple compartments. 
     
     
         6 . A multi-purpose valve assembly for maintaining a predetermined concentration of oxygen and a predetermined concentration of carbon dioxide during storage of a food product within an enclosed package, said multipurpose valve assembly comprising:
 a tubular body having an open end and a closed end that defines a recess between the open and closed ends, and the closed end includes an aperture for venting pressurized gas therethrough;   a retaining member operative for snap-fit engagement with the tubular body that is spaced apart from the closed end of the tubular body; and   a breathable membrane element having a plurality of apertures that is positioned between the closed end of the tubular body and the retaining member, such that the breathable membrane element is positioned adjacent the closed end for respiring a gas from the product through the plurality of apertures in the membrane element at a predetermined transmission rate, to maintain a predetermined a concentration of oxygen and a predetermined concentration of carbon dioxide in the package during storage of the package, and the membrane element is displaceable from the closed end to vent a pressurized gas through the closed end aperture in the closed end during heating of the pouch above a predetermined threshold temperature.   
     
     
         7 . The valve assembly as set forth in  claim 6 , wherein the tubular body includes a flanged portion defined along the open end thereof. 
     
     
         8 . The valve assembly as set forth in  claim 7 , wherein the tubular body includes a rim formed along at least a portion of the flanged portion and operative for snap-fit engagement with the retaining member. 
     
     
         9 . The valve assembly as set forth in  claim 8 , wherein the flanged portion includes an inside edge, the rim being formed along the inside edge. 
     
     
         10 . The valve assembly as set forth in  claim 9 , wherein the tubular body is cylindrically shaped and the membrane element is sized corresponding to the diameter of the recess. 
     
     
         11 . The valve assembly as set forth in  claim 6 , wherein the membrane element is a polypropylene material having a predetermined number of apertures of a predetermined size, to control the transmission rate of gas from the product during storage. 
     
     
         12 . The valve assembly as set forth in  claim 6  wherein the membrane element is a cast polypropylene material having a predetermined number of apertures of a predetermined size, to control the transmission rate of gas from the product during storage. 
     
     
         13 . The valve assembly as set forth in  claim 6 , wherein the closed end includes a plurality of apertures. 
     
     
         14 . The valve assembly as set forth in  claim 13 , wherein each of the plurality of apertures has a substantially sector shape with a diameter of 1.8 mm and a length of 2.6 mm. 
     
     
         15 . A heatable package for a food product comprising:
 a container for the food product having an open end;   a cover for the container that is a sealing film, wherein said cover is sealed the container to enclose the open end of the container;   a multi-purpose valve assembly disposed within the cover, wherein the valve assembly includes:   a tubular body having an open end and a closed end that defines a recess between the open and closed ends, and the closed end includes an aperture for venting a pressurized gas therethrough,   a retaining member operative for snap-fit engagement with the tubular body that is spaced apart from the closed end of the tubular body,   a breathable membrane element having a plurality of apertures that is positioned between the closed end of the tubular body and the retaining member, such that the breathable membrane element is positioned adjacent the closed end for respiring a gas from the product through the plurality of apertures in the membrane element at a predetermined transmission rate, to maintain a predetermined a concentration of oxygen and a predetermined concentration of carbon dioxide in the package during storage.   
     
     
         16 . The package as set forth in  claim 15 , wherein the membrane element is displaceable from the closed end to vent a pressurized gas through the closed end aperture during heating of the package above a predetermined threshold temperature. 
     
     
         17 . The package as set forth in  claim 15 , wherein the membrane element is a polypropylene material having a predetermined number of apertures of a predetermined size to control the transmission rate of gas from the product during storage. 
     
     
         18 . The flexible as set forth in  claim 15  wherein the membrane element is a cast polypropylene material having a predetermined number of apertures of a predetermined size, to control the transmission rate of gas from the product during storage. 
     
     
         19 . The package as set forth in  claim 15 , wherein the closed end includes four apertures, and each aperture has a substantially sector shape with a diameter of 1.8 mm and a length of 2.6 mm.